<template>
  <div class="course">
    <Header></Header>
    <div class="main">
      <!-- 筛选条件 -->
      <div class="condition">
        <ul class="cate-list">
          <li class="title">课程分类:</li>
          <li :class="filter.course_category==0?'this':''" @click="filter.course_category=0">全部</li>
          <li :class="filter.course_category==category.id?'this':''" v-for="category in category_list"
              @click="filter.course_category=category.id" :key="category.name">{{ category.name }}
          </li>
        </ul>

        <div class="ordering">
          <ul>
            <li class="title">筛&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;选:</li>
            <li class="default" :class="(filter.ordering=='id' || filter.ordering=='-id')?'this':''"
                @click="filter.ordering='-id'">默认
            </li>
            <li class="hot" :class="(filter.ordering=='students' || filter.ordering=='-students')?'this':''"
                @click="filter.ordering=(filter.ordering=='-students'?'students':'-students')">人气
            </li>
            <li class="price"
                :class="filter.ordering=='price'?'price_up this':(filter.ordering=='-price'?'price_down this':'')"
                @click="filter.ordering=(filter.ordering=='-price'?'price':'-price')">价格
            </li>
          </ul>
          <p class="condition-result">共{{ course_total }}个课程</p>
        </div>

      </div>
      <!-- 课程列表 -->
      <div class="course-list">
        <div class="course-item" v-for="course in course_list" :key="course.name">
          <div class="course-image">
            <img :src="course.course_img" alt="">
          </div>
          <div class="course-info">
            <h3>
              <router-link :to="'/actual/detail/'+course.id">{{ course.name }}</router-link>
              <span><img src="../assets/img/avatar1.svg" alt="">{{ course.students }}人已加入学习</span></h3>
            <p class="teather-info">
              {{ course.teacher.name }} {{ course.teacher.title }} {{ course.teacher.signature }}
              <span
                  v-if="course.sections>course.pub_sections">共{{ course.sections }}课时/已更新{{
                  course.pub_sections
                }}课时</span>
              <span v-else>共{{ course.sections }}课时/更新完成</span>
            </p>
            <ul class="section-list">
              <li v-for="(section, key) in course.section_list" :key="section.name"><span
                  class="section-title">0{{ key + 1 }}  |  {{ section.name }}</span>
                <span class="free" v-if="section.free_trail">免费</span></li>
            </ul>
            <div class="pay-box">
              <div v-if="course.discount_type">
                <span class="discount-type">{{ course.discount_type }}</span>
                <span class="discount-price">￥{{ course.real_price }}元</span>
                <span class="original-price">原价：{{ course.price }}元</span>
              </div>
              <span v-else class="discount-price">￥{{ course.price }}元</span>
              <span class="buy-now">立即购买</span>
            </div>
          </div>
        </div>
      </div>
      <div class="course_pagination block">
        <el-pagination
            @size-change="handleSizeChange"
            @current-change="handleCurrentChange"
            :current-page.sync="filter.page"
            :page-sizes="[2, 3, 5, 10]"
            :page-size="filter.page_size"
            layout="sizes, prev, pager, next"
            :total="course_total">
        </el-pagination>
      </div>
    </div>
    <!--<Footer></Footer>-->
  </div>
</template>

<script setup>
import {ref, reactive, watch} from "vue";
import Header from "../components/Header.vue"
import Footer from "../components/Footer.vue"
import {reqCourseCategory, reqCourse} from "../api/course.js";

const category_list = ref([]) // 课程分类列表
const course_list = ref([])   // 课程列表
const course_total = ref(0)   // 当前课程的总数量
const filter = reactive({
  course_category: 0, // 当前用户选择的课程分类，刚进入页面默认为全部，值为0
  ordering: "-id",    // 数据的排序方式，默认值是-id，表示对于id进行降序排列
  page_size: 2,       // 单页数据量
  page: 1,
})

async function get_category() {
  let res = await reqCourseCategory()
  category_list.value = res.results
}

async function get_course() {
  // 排序
  let filters = {
    ordering: filter.ordering, // 排序
  };
  // 判决是否进行分类课程的展示
  if (filter.course_category > 0) {
    filters.course_category = filter.course_category;
  }

  // 设置单页数据量
  if (filter.page_size > 0) {
    filters.page_size = filter.page_size;
  } else {
    filters.page_size = 5;
  }

  // 设置当前页码
  if (filter.page > 1) {
    filters.page = filter.page;
  } else {
    filters.page = 1;
  }
  console.log(filters)
  let res = await reqCourse(filters)
  course_list.value = res.results
  course_total.value = res.count

}


function handleSizeChange(val) {
  // 每页数据量发生变化时执行的方法
  filter.page = 1;
  filter.page_size = val;
}

function handleCurrentChange(val) {
  // 页码发生变化时执行的方法
  filter.page = val;
}


watch(() => filter.course_category, () => {
  get_course()
})
watch(() => filter.ordering, () => {
  get_course()
})
watch(() => filter.page_size, () => {
  get_course()
})
watch(() => filter.page, () => {
  get_course()
})

//课程分类
get_category()
//课程列表
get_course()
</script>

<style scoped>
.course {
  background: #f6f6f6;
}

.course .main {
  width: 1100px;
  margin: 35px auto 0;
}

.course .condition {
  margin-bottom: 35px;
  padding: 25px 30px 25px 20px;
  background: #fff;
  border-radius: 4px;
  box-shadow: 0 2px 4px 0 #f0f0f0;
}

.course .cate-list {
  border-bottom: 1px solid #333;
  border-bottom-color: rgba(51, 51, 51, .05);
  padding-bottom: 18px;
  margin-bottom: 17px;
}

.course .cate-list::after {
  content: "";
  display: block;
  clear: both;
}

.course .cate-list li {
  float: left;
  font-size: 16px;
  padding: 6px 15px;
  line-height: 16px;
  margin-left: 14px;
  position: relative;
  transition: all .3s ease;
  cursor: pointer;
  color: #4a4a4a;
  border: 1px solid transparent; /* transparent 透明 */
}

.course .cate-list .title {
  color: #888;
  margin-left: 0;
  letter-spacing: .36px;
  padding: 0;
  line-height: 28px;
}

.course .cate-list .this {
  color: #ffc210;
  border: 1px solid #ffc210 !important;
  border-radius: 30px;
}

.course .ordering::after {
  content: "";
  display: block;
  clear: both;
}

.course .ordering ul {
  float: left;
}

.course .ordering ul::after {
  content: "";
  display: block;
  clear: both;
}

.course .ordering .condition-result {
  float: right;
  font-size: 14px;
  color: #9b9b9b;
  line-height: 28px;
}

.course .ordering ul li {
  float: left;
  padding: 6px 15px;
  line-height: 16px;
  margin-left: 14px;
  position: relative;
  transition: all .3s ease;
  cursor: pointer;
  color: #4a4a4a;
}

.course .ordering .title {
  font-size: 16px;
  color: #888;
  letter-spacing: .36px;
  margin-left: 0;
  padding: 0;
  line-height: 28px;
}

.course .ordering .this {
  color: #ffc210;
}

.course .ordering .price {
  position: relative;
}

.course .ordering .price::before,
.course .ordering .price::after {
  cursor: pointer;
  content: "";
  display: block;
  width: 0px;
  height: 0px;
  border: 5px solid transparent;
  position: absolute;
  right: 0;
}

.course .ordering .price::before {
  border-bottom: 5px solid #aaa;
  margin-bottom: 2px;
  top: 2px;
}

.course .ordering .price::after {
  border-top: 5px solid #aaa;
  bottom: 2px;
}

.course .ordering .price_up::before {
  border-bottom-color: #ffc210;
}

.course .ordering .price_down::after {
  border-top-color: #ffc210;
}

.course .course-item:hover {
  box-shadow: 4px 6px 16px rgba(0, 0, 0, .5);
}

.course .course-item {
  width: 1100px;
  background: #fff;
  padding: 20px 30px 20px 20px;
  margin-bottom: 35px;
  border-radius: 2px;
  cursor: pointer;
  box-shadow: 2px 3px 16px rgba(0, 0, 0, .1);
  /* css3.0 过渡动画 hover 事件操作 */
  transition: all .2s ease;
}

.course .course-item::after {
  content: "";
  display: block;
  clear: both;
}

/* 顶级元素 父级元素  当前元素{} */
.course .course-item .course-image {
  float: left;
  width: 423px;
  height: 210px;
  margin-right: 30px;
}

.course .course-item .course-image img {
  max-width: 100%;
  max-height: 210px;
}

.course .course-item .course-info {
  float: left;
  width: 596px;
}

.course-item .course-info h3 a {
  font-size: 26px;
  color: #333;
  font-weight: normal;
  margin-bottom: 8px;
}

.course-item .course-info h3 span {
  font-size: 14px;
  color: #9b9b9b;
  float: right;
  margin-top: 14px;
}

.course-item .course-info h3 span img {
  width: 11px;
  height: auto;
  margin-right: 7px;
}

.course-item .course-info .teather-info {
  font-size: 14px;
  color: #9b9b9b;
  margin-bottom: 14px;
  padding-bottom: 14px;
  border-bottom: 1px solid #333;
  border-bottom-color: rgba(51, 51, 51, .05);
}

.course-item .course-info .teather-info span {
  float: right;
}

.course-item .section-list::after {
  content: "";
  display: block;
  clear: both;
}

.course-item .section-list li {
  float: left;
  width: 44%;
  font-size: 14px;
  color: #666;
  padding-left: 22px;
  /* background: url("路径") 是否平铺 x轴位置 y轴位置 */
  background: url("/src/assets/img/play-icon-gray.svg") no-repeat left 4px;
  margin-bottom: 15px;
}

.course-item .section-list li .section-title {
  /* 以下3句，文本内容过多，会自动隐藏，并显示省略符号 */
  text-overflow: ellipsis;
  overflow: hidden;
  white-space: nowrap;
  display: inline-block;
  max-width: 200px;
}

.course-item .section-list li:hover {
  background-image: url("/src/assets/img/play-icon-yellow.svg");
  color: #ffc210;
}

.course-item .section-list li .free {
  width: 34px;
  height: 20px;
  color: #fd7b4d;
  vertical-align: super;
  margin-left: 10px;
  border: 1px solid #fd7b4d;
  border-radius: 2px;
  text-align: center;
  font-size: 13px;
  white-space: nowrap;
}

.course-item .section-list li:hover .free {
  color: #ffc210;
  border-color: #ffc210;
}

.course-item {
  position: relative;
}

.course-item .pay-box {
  position: absolute;
  bottom: 20px;
  width: 600px;
}

.course-item .pay-box::after {
  content: "";
  display: block;
  clear: both;
}

.course-item .pay-box .discount-type {
  padding: 6px 10px;
  font-size: 16px;
  color: #fff;
  text-align: center;
  margin-right: 8px;
  background: #fa6240;
  border: 1px solid #fa6240;
  border-radius: 10px 0 10px 0;
  float: left;
}

.course-item .pay-box .discount-price {
  font-size: 24px;
  color: #fa6240;
  float: left;
}

.course-item .pay-box .original-price {
  text-decoration: line-through;
  font-size: 14px;
  color: #9b9b9b;
  margin-left: 10px;
  float: left;
  margin-top: 10px;
}

.course-item .pay-box .buy-now {
  width: 120px;
  height: 38px;
  background: transparent;
  color: #fa6240;
  font-size: 16px;
  border: 1px solid #fd7b4d;
  border-radius: 3px;
  transition: all .2s ease-in-out;
  float: right;
  text-align: center;
  line-height: 38px;
  position: absolute;
  right: 0;
  bottom: 5px;
}

.course-item .pay-box .buy-now:hover {
  color: #fff;
  background: #ffc210;
  border: 1px solid #ffc210;
}

.course .course_pagination {
  margin-bottom: 60px;
  text-align: center;
}

.el-pagination {
  display: flex;
  justify-content: center; /* 水平居中 */
  align-items: center; /* 垂直居中 */
}
</style>
